Well, think about global warming from the point of view of someone who grew up taking Ayn Rand seriously, believing that the untrammeled pursuit of self-interest is always good and that government is always the problem, never the solution. Along come some scientists declaring that unrestricted pursuit of self-interest will destroy the world, and that government intervention is the only answer. It doesn’t matter how market-friendly you make the proposed intervention; this is a direct challenge to the libertarian worldview.